1. Field of the Invention
The present invention relates generally to an improved chassis for a travel trailer vehicle, and in particular to a supplemental support frame for the chassis that supports the axles and allows for increased storage capability.
2. Description of Related Art
The term xe2x80x9ctravel trailerxe2x80x9d as used herein refers to a towed vehicle capable of serving as a living quarters. Travel trailers are constructed in a variety of sizes and shapes, and most typically comprise living quarters of fixed or expandable size for use when the vehicle is not moving. Travel trailers are a popular item for people who like to travel about the country in extended trips because the travelers can store everything needed in the travel trailer without unpacking or transferring the food, equipment, and supplies.
Travel trailers are comprised of the living quarters or xe2x80x9cshellxe2x80x9d mounted on a vehicle xe2x80x9cchassisxe2x80x9d designed especially for travel trailers. The motor vehicle industry manufactures a variety of towable chassis that can support different shells depending on the needs and amenities sought. The shell is a self-contained structure comprising walls, a roof, and a floor that is seated and supported on the chassis.
To support the shell and provide rigidity to the chassis, the chassis frame includes two parallel elongate beam members, commonly referred to as chassis rails, that extend between the front and rear ends of the chassis. These chassis rails are normally constructed of steel beams with an I-beam or channel-shaped cross-section. In addition to functioning as the main support structure for the chassis, the chassis rails are used to mount the axles of the chassis. The chassis rails are spaced apart a specific distance to support the axles of the vehicle. The axles that support the wheels are traditionally mounted directly to the two chassis rails, which in turn influences the spacing between the two beams.
A wide spacing between the chassis rails allows for a wider track for the axles. A wide track provides a smoother ride and better handling, with more stability against tipping overxe2x80x94a concern with high profile vehicles such as travel trailers. However, a preference for a wide spacing of the chassis rails is offset by the relationship of the spacing of the rails to the available storage space under the shell. The two rails, since they run predominantly down the longitudinal direction of the chassis, establish a boundary that storage space cannot usually extend beyond. Thus the wider the chassis rails, the less storage capacity is available under the travel trailer to store supplies and equipment. However, narrowing the spacing between the two rails affects the track for the wheels, which is optimally wider than the position established by the normal spacing of the rails.
Since travel trailers are used for long journeys and travel to isolated areas, available storage space is a critical concern. Manufactures have tried to maximize the storage space underneath the shell, but the presence of the chassis rails limits beneath the floor of the shell impacts how much space is available. The manufacturers are therefore left with the decision to narrow the chassis rails at the expense of safety and driving stability, or widen the chassis rails at the expense of limiting the available storage space for the travel trailer.
It is apparent from the foregoing that there is a need for a new and improved travel trailer and, more specifically, for a travel trailer which overcomes the problems associated with a lack of easily-accessible space for personal goods in a travel trailer. To overcome the shortcomings of the existing art, the present invention provides a supplemental chassis platform comprising a box structure that is rigidly mounted to the main chassis rails. The supplemental platform assumes the role of axle support from the chassis rails, where a plurality of cross beams cooperate to form a framework that supports the axle assembly outside of the chassis"" twin main rails. With the axles supported by the box section, the chassis rails"" spacing can be reduced to increase the storage space available under the shell.
In a preferred embodiment, the box section uses three elongate steel tubes to form cross or traverse members for lateral support. The traverse members pass directly through the main rails at pre-cut holes and are welded at the junction between the traverse members and the chassis rails. By welding the cross members around the juncture""s circumference, a strong attachment to both rails is achieved for each cross member. Further, by passing the cross members through the main chassis rails the axles supported on the box platform are kept in the same plane as the bottom of the rails, allowing an increase in storage above the rails while keeping the height of the trailer as it would have been without the added structure. Each traverse cross member is attached at respective ends to first and second side beams to form a rigid box support or platform upon which an axle assembly can be mounted. The side beams are positioned outside of the main chassis rails to extend the axle support beyond the main chassis rails and provide wide track attachment points for the axles. Further, each cross member attaches to the side beams at locations corresponding to axle support attachment points. The loads from the axles through the axle support are thus translated into the main beam through the cross members.
The particular travel trailer chassis illustrated in the drawings utilizes the concepts of this invention as are defined in the appended claims. Those skilled in the field of the construction and design of travel trailer chassis will realize that these operative concepts may be easily employed in travel trailer chassis which differ significantly in appearance or construction from the chassis illustrated through the use and exercise of routine engineering skill in the noted field. Further, other objects and merits and a fuller understanding of the present invention will be obtained by those having ordinary skill in the art when the following detailed description of the preferred embodiment is read in conjunction with the accompanying drawings. Therefore, the accompanying drawings are not to be considered as limiting this invention.